Feeder for screw blanks and serrated washers

ABSTRACT

Vibratory track means for serially feeding washers, the track means including means providing an upwardly facing first ledge portion for supporting peripheral edge portions of the washers, an upwardly extending first wall portion extending along and bounding the first ledge portion, and an overhanging, downwardly facing portion extending outwardly from the first wall portion by an amount preferably not substantially greater than the crosssectional width of the first ledge portion. The track means also includes means providing a second upwardly facing ledge portion for supporting the diametrically opposite peripheral edge portions of the washers and an upwardly extending second wall portion extending along and bounding the second ledge portion and facing the said first wall portion, the track means being devoid of any surface overhanging this second ledge portion.

United States Patent Brown et al.

1 Feb. 1, 1972 [72] Inventors: John B. Brown; Raymond L. Alexander, bothof Indianapolis, Ind.

[73} Assignee: Moorfeed Corporation, Indianapolis, Ind.

[22] Filed: Mar. 25, 1970 [21] Appl. No.: 22,635

Primary ExaminerCharles W. Lanham Assistant Examiner-E. M. CombsAttorney-Hood, Gust, Irish & Lundy 57] ABSTRACT Vibratory track meansfor serially feeding washers, the track means including means providingan upwardly facing first ledge portion for supporting peripheral edgeportions of the washers, an upwardly extending first wall portionextending along and bounding the first ledge portion, and anoverhanging, downwardly facing portion extending outwardly from thefirst wall portion by an amount preferably not substantially greaterthan the cross-sectional width of the first ledge portion. The trackmeans also includes means providing a second upwardly facing ledgeportion for supporting the diametrically opposite peripheral edgeportions of the washers and an upwardly extending second wall portionextending along and bounding the second ledge portion and facing thesaid first wall portion, the track means being devoid of any surfaceoverhanging this second ledge portion.

1 1 Claims, 9 Drawing Figures PATENIEB FEM m2 DAY INVENTORS JOHN 8.BROWN 2 RAYMOND L. ALEXANDER B I 4 4 W W W ATTORN S FEEDER FOR SCREWBLANKS AND SERRATED WASHERS It is a primary object of our invention toprovide a vibratory track means for serially feeding washers, whichtrack means is particularly suited for feeding small, lightweightserrated washers having either internal teeth or external teeth.

Another object of our invention is to provide an assembly apparatusincluding a pair of vibratory track means, one of which feeds serratedwashers and the other one of which feeds screw blanks to be mated withthe serrated washers.

Our invention relates generally to vibratory feeders and hoppers of thetype shown in the Balsiger et al., US. Pat. No. 2,609,914. Vibratoryfeeders generally include a bowl into which parts are dumped and aspiral track leading upwardly about the wall of the bowl. As the bowl isvibrated, the parts move from the bottom of the bowl onto the track andupwardly about the track. We have been constructing vibratory feederswhich will feed and mate screw blanks and washers and then feed themated screw blanks and washers to a conventional thread rollingapparatus which rolls threads on the shanks of the screw blanks tocapture the washers thereon.

Our preferred vibratory feeder includes a bowl for feeding the screwblanks and an annular pan for feeding washers, the pan beingconcentrically disposed about the bowl and connected thereto forvibration therewith. It is our practice, to bring the screw blanks alonga downwardly inclining trackway, supporting the screw blanks by theirheads with their shank portions hanging downwardly, and then to bringwashers along an upwardly inclining trackway which is disposed justbelow the trackway on which the screw blanks are carried. As the screwblanks and washers move along their respective trackways which arepreferably in vertical registry, the shanks of the screw blanks willengage and extend into the openings in the washers. This general conceptis disclosed in the copending Raymond L. Alexander US. Pat. applicationSer. No. 680,676 filed Nov. 6, 1967 now US. Pat. No. 3,523,316, issuedAug. 11, 1970.

I-Ieretoforc, it has been difficult, if not'impossible, to feed verysmall, lightweight serrated washers serially along the trackway byvibration of the trackway. This has been especially true in the case ofexternal tooth serrated washers. The washers are so light that they donot tend to move along a vibrating track as well as larger, heavierwashers. The hesitancy of some washers to move causes engagement ormeshing of the washer teeth. When the teeth mesh or engage, the washerstend to lock together and to stop movement along the track.

To our knowledge and belief, heretofore, trackways for feeding washershave been defined either by forming inwardly extending, generallyrectangular grooves in the facing surfaces of members or by forming anopen-topped slot in one or more members. These two types of trackwaysare shown in the accompanying drawings.

We believe that a washer which has an outer diameter of about one-halfinch and a thickness of about 0.060 inch is considered a small,lightweight washer. Our trackway is particularly suited for an evensmaller, lighter washer such as a washer having an outer diameter offive-sixteenth inch and a thickness of one thirty-second inch. It willbe appreciated, however, that our trackway may be used for feeding anyconventional washer.

To the accomplishment of the above and related objects, our inventionmay be embodied in the forms illustrated in the accompanying drawings,attention being called to the fact, however, that the drawings areillustrative only and that change may be made in the specificconstructions illustrated and described, so long as the scope of theappended claims is not violated.

In the drawings:

FIG. 1 is a perspective view of a conventional external tooth serratedwasher;

FIG. 1a is a perspective view of a conventional internal tooth serratedwasher;

FIG. 2 is a perspective view of an assembly apparatus comprising thetrack means of the present invention;

FIG. 3 is an elevational view of the track means of the presentinvention;

FIG. 4 is an enlarged fragmentary and sectional perspective view of theentrance end portion of the track means of the present invention, thisview being taken along the section line 44 in FIG. 3; 7

FIG. 5 is a fragmentary sectional view taken along the line 55 in FIG.3;

FIG. 6 is a fragmentary sectional view of a prior art track y;

FIG. 7 is another fragmentary sectional view of another prior arttrackway; and I FIG. 8 is an enlarged, fragmentary sectional view of atrack way formed in accordance with the present invention.

Referring now to the drawings, and particularly to FIGS. 1, la and 2, itwill be seen that we have shown a vibratory feeder 10 comprising a bowl12 and an annular pan 14 disposed peripherally about the bowl l2 andrigidly fastened thereto for vibration therewith. Reference is made tothe copending Raymond L. Alexander application Ser. No. 680,676 filedNov. 6, I967 now US. Pat. No. 3,523,316 for a disclosure of the type offeeder indicated at 10. As discussed in this copending application,screw blanks or screws are placed in the bowl 12 and washers are placedin the annular pan 14. The feeder 10 includes a spiral track 16 forconveying the screws or screw blanks upwardly from the bottom of thebowl 12 to a point indicated at 18. At this point 18, which is the exitend of the track 16, as is now well known and as is disclosed incopending application Ser. No. 680,676, now US. Pat. No. 3,523,316 thescrews or screw blanks are suspended by their heads.

Further, the feeder 10 comprises a track which inclines upwardly aboutthe bowl 12 from the bottom of the pan 14 to feed serially washers fromthe pan, the exit end of this track being indicated at 20 in FIG. 3. Itwill be appreciated that the exit end point 18 is just above andpreferably in vertical registry with the exit end point 20.

It is an object of our invention to provide a track system or trackmeans, indicated generally at 22, for receiving the screws or screwblanks from the exit end point 18 and the washers from the exit endpoint 20 and conveying these screws or screw blanks and washers to thepoint at which they are mated. This track system 22 is mounted on thewall 24 which is the outside wall of the bowl 12. We show a track 26which is arranged to convey triated screws or screw blanks and washersaway from the exit end of the track system 22.

The feeder 10 comprises a base 18 upon which the bowl l2 and the pan 14as well as the track system 22 are mounted for vibration. Specifically,the bowl 12 with the pan l4 and track system 22 rigidly connectedthereto is mounted upon the platform 28 by means of springs and anelectromagnetic motor is provided for vibrating the bowl and pan. Suchvibrator-type feeders are well known and need not be discussed, indetail, in this description. See, for instance, the Balsig'er et al.,US. Pat. No. 2,609,914 issued Sept. 9, 1952. Reference is made to thisBalsiger et al., patent for a description of the manner in which thebowl l2 and the pan 1 are vibrated as well as the manner in which partsmove about spirally inclined tracks.

In this description, and in the claims appended hereto, the term screw"includes a screw blank, i.e., a blank which is fed to a thread-rollingapparatus so that a thread can be formed on its shank.

In FIG. 1, we show a conventional external tooth-serrated washer 30 andin FIG. la, we show a conventional internal tooth-serrated washer 32.The feeder l0 and the track means 22 are particularly suited for feedingand mating such serrated washers with screw blanks. In this descriptionand in the drawings, the screw blanks being fed from the bowl 12 areindicated at 34 and the washers being fed from the pan 14 are indicatedat 30.

Referring now to FIGS. 6 and 7, it will be seen that we have illustratedcross sections of previously used trackways for washers. In FIG. 7, weshow grooves 36, 38 formed respectively in spaced apart members 36, 38'to support diametrically opposite peripheral edge portions of washers,such as indicated at 30. Such a trackway is disclosed in the aforesaidAlexander application Ser. No. 680,676 now U.S. Pat. No. 3,523,316.Specifically, the member 36' extends peripherally about a portion of abowl, such as the bowl l2, and the member 38 extends peripherally aboutthe member 36. The grooves 36, 38 are formed, respectively, in the outerand inner surfaces of the members 36', 38' to provide a trackway forconveying washers 30. In FIG. 6, we show rabbets 40, 42 formed,respectively, in members 40', 42' to provide a trackway for conveyingwashers such as indicated at 30. Specifically, the member 40' extendsperipherally about a bowl wall and the member 42 extends peripherallyabout the member 40. The trackway provided by the rabbeted members 40,42' is open at its top and the washers 30 are held downwardly thereinonly by gravity. In the structure of FIG. 7, it will be appreciated thatthe washer 30 is confined or restrained against significant movement inany direction except along the direction of the grooves '36, 38.

These previously used trackways shown in FIGS. 6 and 7 have been foundto be totally inadequate for feeding small, lightweight, serratedwashers. In the trackway structure of FIG. 7, the washers tend to jamtogether to resist movement therealong. In the structure of FIG. 6, atthe slightest hesitancy in its movement, a small lightweight, serratedwasher will jump up out of or climb up out of the trackway. The trackwayof our present invention is designed to solve these problems.

Referring again to FIGS. 2-5, it will be seen that there is aperipherally extending platform member 50 inclining upwardly about theouter wall 24 of the bowl 12, this platform member being removablyfastened to the wall 24 by fastening means such as indicated at 51. Afirst vertically extending member is mounted on this platform member 50to extend peripherally about a portion of the sidewall 24 and a secondvertically extending member 54 is mounted on the member 50 radiallyoutwardly from the member 52 to extend peripherally about the sameportion of the wall 24. These two members 52, 54 are spaced apart todefine a space 56 which receives the shanks of the screw blanks 34. Thetwo members 52, 54 may be welded or otherwise securely fastened to theplatform member 50. We provide a groove 58 which inclines upwardly aboutthe outer peripheral surface of the member 52 and we rabbet the upperedge of the member 54 as indicated at 60. The groove 58 and the rabbet60 spirally incline upwardly at the same rate.

In accordance with our present invention, the groove 58 provides a firstledge portion 62 for supporting peripheral edge portions of such washers30, an upwardly extending first wall portion 64 extending along andbounding the first ledge portion 62, and an overhanging, downwardlyfacing portion 66 extending outwardly from the wall portion 64 by anamount which preferably is not substantially greater than thecross-sectional width of the first ledge portion 62. For instance, webelieve that the portion 66 should not extend outwardly to the point atwhich it will overlie a significant portion of the opening in a washercarried in the trackway provided by the groove 58 and rabbet 60. Thereason for this will become apparent as the description proceeds to thediscussion of mating screw blanks with washers. The entrance end of thisgroove 58 is beveled as indicated at 68 to provide a sort of guidingsurface which inclines upwardly relative to the first ledge portion 62.That is, as washers 30 leave the exit end 20, the beveled surface 68tends to guide a peripheral edge portion of the washer into the groove58.

The rabbet 60 in the member 54 provides a second upwardly facing ledgeportion 70 for supporting the diametrically opposite peripheral edgeportions of such washers 30, this second ledge portion extendingalongside the first ledge portion 62, and an upwardly extending secondwall portion 72 extending along and bounding the second ledge portion 70and facing the said first wall portion 64. Now, it will be appreciatedthat the trackway provided by the groove 58 and the rabbet 60 is devoidof any surface overhanging the said second ledge portion 70. In otherwords, there is an overhanging portion 66 in vertical registry with thefirst ledge portion 62 but there is no such overhanging portion invertical registry with the second ledge portion 70. The differencesbetween the trackway structure of our present invention and the priortrackway structures of FIGS. 6 and 7 will, therefore, be apparent.

In FIG. 8, which is slightly enlarged, we show the first ledge portion62, first wall portion 64, overhanging portion 66, second ledge portion70 and second wall portion 72 formed in a single member and indicate, bymeans of dashed lines 74, that the surfaces which engage thediametrically opposite peripheral edge portions of a washer 30 may beformed in a single member so that the first ledge portion 62 and secondledge portion 70 are in effect the same surface formed in the member.Thus, in this description and in the claims appended hereto, the firstand second ledge portions 62, 70 may be portions of the same surface inthe same member or they may be, as shown in FIGS. 2-5, surfaces formedin adjacent members with a space therebetween. It will be appreciatedthat the space between the ledge surfaces is required to receive theshanks of screw blanks which are mated with the washers riding thereon.The dashed lines 74 represent such a space which may start at any pointalong the trackway provided by the groove 58 and rabbet 60.

The upper, outer edge of the member 52 provides a third ledge portionfor supporting peripheral edge portions of the heads of the screw blanks34, this third ledge portion being disposed above and in verticalregistry with the first ledge portion 62. The diametrically oppositeperipheral edge portions of the heads of the screws 34 are supported bya fourth ledge portion 82 which is provided by a flat metal strip 84extending alongside the ledge portion 80. This fourth ledge portion 82is disposed above and in vertical registry with the second ledge portion70. The strip 84 is supported by means of vertically extending posts 86,the strip being fastened to the posts by fastening means such asindicated at 88 and the posts being fastened to the platform member 50by fastening means such as indicated at 90.

Thus, the screw blanks 34 are conveyed along the upper track meansdefined by the ledge portions 80, 82 and the washers 30 are conveyedalong a lower track means defined by the ledge portions 62, 70. Asviewed in FIG. 3, it will be appreciated that the upper ledge portions80, 82 incline downwardly relative to the lower ledge portions 62, 70 sothat the shanks of the screw blanks 34 moving along the upper ledgeportions will engage and extend through the openings in the washers 30moving along the lower ledge portions. That is, the screw blanks are fedserially at generally a constant rate and the washers 30 are fedserially at generally a constant rate so that the shank portions of thescrew blanks will engage and extend through the washers movingtherebelow. The exit end of the upper track means, i.e., upper ledgeportions 80, 82, indicated at 91 is the point at which the screw blankswill drop into full engagement with their mating washers. That is, atthis exit end point 91, the heads of the screw blanks are no longersupported so that the screw blank drops downwardly. The track 26, whichreceives mated screw blanks and washers from the exit end of the tracksystem 22, is arranged to support the diametrically opposite edgeportions of the washers leaving the trackway provided by the groove 58and rabbet 60. Since each screw blank 34 is engaged with a washer 30with its head resting on the upper surface of the washer, the matedscrew blanks and washers are carried on and along the track 26.

The exit end portion of the strip member 84 is sharpened as indicated at91 so that this member 84 can be used with shorter posts 86 and adifferent member 52 to mate extremely short screw blanks 34 with washers30. That is, in some cases, the member 84 may be positioned so that itsexit end 91 is just, for instance, one-eighth of an inch above thesecond ledge portion 70 disposed therebelow.

We show an air jet means 92 disposed on the track system 22 and arrangedto facilitate the mating of screw blanks and washers and the moving ofsuch mated screw blanks and washers. The jet means 92 includes an airinput line 94 and a jet line 96 arranged to direct a jet of airdownstream, i.e., in the direction of movement of the screw blanks 34and washers 30, at such screw blanks and washers after they are engaged.Specifically, we prefer that the jet line 96 be positioned to direct ajet of air at the shank portions of screw blanks which have just enteredthe opening in a washer. This blast of air provided by the jet line 96rapidly moves the screw blank and the washer through which its shankextends to the right as viewed in FIG. 3 to clear the trackway so thatanother screw blank can engage and extend into another washer. Thismovement by the jet of air is in addition to the movement provided bythe vibratory motion of the track system 22.

In the illustrative embodiment, we show a guide member 98 which ismounted on the posts 86 to be under the strip member 84. The radiallyinner edge of this peripherally extending member 98 acts as a guide forthe shank portions of the screw blanks 34 to keep the shank portionsdirected downwardly toward the washers moving therebelow.

The dimensions of each trackway provided by a groove 58 and rabbet 60will depend, of course, on the dimensions of the washer to be carriedalong the trackway. We offer the following formulas as guidelines forconstructing trackways, assuming that:

OD=Outer diameter of washer;

ID=lntemal diameter of washer;

T=Thickness of washer;

W=Width of trackway or distance between 64 and 72;

D=Depth of trackway or height of walls 64 and 72; and

L=Cross-sectional width of ledge portions 62 and 70 and overhang 66.

Then:

W=0D+0.020 to 0.030 inch;

D=T+60% T; and

While D is shown above as being calculated on the basis of adding to thethickness Tof the washer a percentage of T ranging from 10 to 60percent, we have found that, in most cases, D will be equal to T+50% T.This will vary of course with the type of washer being fed.

What is claimed is:

l. Vibratory track means for serially feeding washers longitudinallytherealong by vibratory movement, said track means including meansproviding an upwardly facing first ledge portion extending therealongfor supporting peripheral edge portions of such washers, an upwardlyextending first wall portion extending along and bounding said firstledge portion, an overhanging, downwardly facing portion extendingoutwardly from and along said first wall portion by an amount notsubstantially greater than the cross-sectional width of said first ledgeportion, a second upwardly facing ledge portion for supporting thediametrically opposite peripheral edge portions of such Washers, saidsecond ledge portion extending longitudinally alongside said first ledgeportion, and an upwardly extending second wall portion extending alongand bounding said second ledge portion and facing said first wallportion, said track means being devoid of any surface overhanging saidsecond ledge portion.

2. The invention of claim 1 in which the ledge portions are spaced apartby an amount substantially equal to or greater than the internaldiameter of such washers and less than the outer diameter of suchwashers.

3. The invention of claim 1 in which the distance between said firstledge portion and said overhanging, downwardly facing portion is from 10to 60 percent greater than the thickness of such washers and in whichthe cross-sectional width of said first ledge portion and saidoverhanging portion is less than one-half the difference between theouter diameter and the internal diameter of such washers.

4. The invention of claim 3 in which the ledge portions are spaced apartby a distance greater than the internal diameter of such washers andless than the outer diameter of such washers.

5. The invention of claim 4 in which the height of said second wallportion is from 10 to 60 percent greater than the thickness of suchwashers.

6. The invention of claim 3 in which said track means is provided withan entrance end to which such washers are fed and in which saidoverhanging, downwardly facing portion is provided, at said entranceend, with a beveled surface inclining upwardly away from said firstledge portion.

7. The invention of claim 1 including an upper track means for seriallyfeeding screws for mating with such washers, said upper track meansincluding an exit end portion disposed above and in vertical registrywith a portion of said first mentioned track means, said exit endportion including a third ledge portion for supporting peripheral edgeportions of the heads of such screws and a fourth ledge portion forsupporting the diametrically opposite peripheral edge portions of theheads of such screws, said third ledge portion being disposed above andin vertical registry with said first ledge portion and said fourth ledgeportion being disposed above and in vertical registry with said secondledge portion, said third and fourth ledge portions being spaced apartto receive therebetween the downwardly extending shanks of such screws,and said third and fourth ledge portions inclining downwardly relativeto said first and second ledge portions so that the shanks of suchscrews moving along said third and fourth ledge portions will engage andextend through the openings in such washers moving along said first andsecond ledge portions.

8. The invention of claim 7 in which said means providing said firstledge portion, first wall portion and said overhanging, downwardlyfacing portion includes a member formed with an elongated, generallyrectangularly shaped groove in an upwardly extending surface thereof,the lower surface of said groove providing said first ledge portion,-the bottom of said groove providing said first wall portion and theupper surface of said groove providing said downwardly facing portion.

9. The invention of claim 8 in which said member is formed with an upperedge inclining downwardly toward said groove to provide said third ledgeportion.

10. The invention of claim 9 including a vibratory feeder bowl forfeeding such screws and an annular pan for feeding such washers, saidpan being disposed peripherally about said bowl and rigidly connectedthereto for vibration therewith, said member being formed about agenerally vertical axis coinciding generally with the axis of said bowl,said member being mounted to extend about the periphery of said bowl andabove said pan with said groove formed in the outer periphery of saidmember, and in which said upper track means includes a strip extendingperipherally about said bowl and inclining downwardly to provide saidfourth ledge portion, and means for mounting said strip.

11. The invention of claim 7 including air jet means disposed adjacentto said exit end portion and arranged to direct a jet of air downstreamat such screws and washers after they are engaged.

1. Vibratory track means for serially feeding washers longitudinallytherealong by vibratory movement, said track means including meansproviding an upwardly facing first ledge portion extending therealongfor supporting peripheral edge portions of such washers, an upwardlyextending first wall portion extending along and bounding said firstledge portion, an overhanging, downwardly facing portion extendingoutwardly from and along said first wall portion by an amount notsubstantially greater than the cross-sectional width of said first ledgeportion, a second upwardly facing ledge portion for supporting thediametrically opposite peripheral edge portions of such washers, saidsecond ledge portion extending longitudinally alongside said first ledgeportion, and an upwardly extending second wall portion extending alongand bounding said second ledge portion and facing said first wallportion, said track means being devoid of any surface overhanging saidsecond ledge portion.
 2. The invention of claim 1 in which the ledgeportions are spaced apart by an amount substantially equal to or greaterthan the internal diameter of such washers and less than the outerdiameter of such washers.
 3. The invention of claim 1 in which thedistance between said first ledge portion and said overhanging,downwardly facing portion is from 10 to 60 percent greater than thethickness of such washers and in which the cross-sectional width of saidfirst ledge portion and said overhanging portion is less than one-halfthe difference between the outer diameter and the internal diameter ofsuch washers.
 4. The invention of claim 3 in which the ledge portionsare spaced apart by a distance greater than the internal diameter ofsuch washers and less than the outer diameter of such washers.
 5. Theinvention of claim 4 in which the height of said second wall portion isfrom 10 to 60 percent greater than the thickness of such washers.
 6. Theinvention of claim 3 in which said track means is provided with anentrance end to which such washers are fed and in which saidoverhanging, downwardly facing portion is provided, at said entranceend, with a beveled surface inclining upwardly away from said firstledge portion.
 7. The invention of claim 1 including an upper trackmeans for serially feeding screws for mating with such washers, saidupper track means including an exit end portion disposed above and invertical registry with a portion of said first mentioned track means,said exit end portion including a third ledge portion for supportingperipheral edge portions of the heads of such screws and a fourth ledgeportion for supporting the diametrically opposite peripheral edgeportions of the heads of such screws, said third ledge portion beingdisposed above and in vertical registry with said first ledge portionand said fourth ledge portion being disposed above and in verticalregistry with said second ledge portion, said third and fourth ledgeportions being spaced apart to receive therebetween the downwardlyextending shanks of such screws, and said third and fourth ledgeportions inclining downwardly relative to said first and second ledgeportions so that the shanks of such screws moving along said third andfourth ledge portions will engage and extend through the openings insuch washers moving along said first and second ledge portions.
 8. Theinvention of claim 7 in which said means providing said first ledgeportion, first wall portion and said overhanging, downwardly facingportion includes a member formed with an elongated, generallyrectangularly shaped groove in an upwardly extending surface thereof,the lower surface of said groove providing said first ledge portion, thebottom of said groove providing said first wall portion and the uppersurface of said groove providing said downwardly facing portion.
 9. Theinvention of claim 8 in which said member is formed with an upper edgeinclining downwardly toward said groove to provide said third ledgeportion.
 10. The invention of claim 9 including a vibratory feeder bowlfor feeding such screws and an annular pan for feeding such washers,said pan being disposed peripherally about said bowl and rigidlyconnected thereto for vibration therewith, said member being formedabout a generally vertical axis coinciding generally with the axis ofsaid bowl, said member being mounted to extend about the periphery ofsaid bowl and above said pan with said groove formed in the outerperiphery of said member, and in which said upper track means includes astrip extending peripherally about said bowl and inclining downwardly toprovide said fourth ledge portion, and means for mounting said strip.11. The invention of claim 7 including air jet means disposed adjacentto said exit end portion and arranged to direct a jet of air downstreamat such screws and washers after they are engaged.